Bario

The glass tetra, Bario oligolepis, is a characin from northern South America, with populations in Venezuela, the Guianas, Peru and Brazil. One of a handful of species that closely resemble the red-eye tetra, it is seen much less often in the hobby and is also known as the glassy tetra. It inhabits slow-moving rivers, tributaries and floodplain lakes. Very peaceful, it does not compete well with boisterous or much larger tankmates.

The red-eye tetra, Bario sanctaefilomenae, is a characin from Brazil, Paraguay and Argentina, living mostly in clear rivers that feed the Pantanal. All fish in the trade are captive-bred in huge numbers and are unfussy about water chemistry and diet. Somewhat boisterous, it suits a community of active tankmates such as similarly sized tetras, rainbowfish and barbs, and can intimidate sedate species such as anabantoids or dwarf cichlids.